Phase Control Technology Of Ac Power Regulator

The core of the industrial power conditioner design lies in the precise control of the AC power waveform. Silicon control resonators (SCRs) and triacs (TRIACs), as semiconductor switching elements, form the basis for phase-shift control schemes in most AC voltage regulation systems. An SCR is a PNPN semiconductor switching element that uses a gate trigger signal to open the conduction path, thus controlling the current.

Inside the electrical power conditioner device, the phase-shift control strategy is based on adjusting the on-time within each AC cycle. The control circuit extracts the phase information of the AC power supply and dynamically generates trigger pulses to change the conduction angle of the SCR or TRIAC. Changes in the conduction angle directly affect the voltage waveform and energy transfer status at the load.

The TRIAC element is designed to be equivalent to two anti-parallel SCRs, enabling it to respond to gate signals in both the positive and negative half-cycles of the AC power supply, achieving bidirectional power control. This architecture is very common in single phase power conditioner and is beneficial for achieving fine waveform management of AC loads.